import React, { Component } from 'react'
import './index.css'

export default class Footer extends Component {

    // 全选checkedbox的回调
    handleCheckAll = (event) =>{
        this.props.checkAllTodo(event.target.checked)
    }

    // 清除已完成的任务回调
    handleClearAllDone = () =>{
        this.props.clearAllDone()
    }

    render() {
        const {todos}  = this.props
        // 已完成的个数
        const doneCount = todos.reduce((prev,todo)=>{return prev+(todo.done? 1 : 0)},0)
        // console.log('%',doneCount)
        // 完成的总数
        const total = todos.length
        // console.log(total);
        
        return (
            <div className="todo-footer">
                  <label>
                    <input type="checkbox" onChange={this.handleCheckAll} checked={(doneCount ===total&&total !==0) ? true:false}/>
                  </label>
                  <span>
                    <span>已完成{doneCount}</span> / 全部{total}
                  </span>
                  <button onClick={this.handleClearAllDone} className="btn btn-danger">清除已完成任务</button>
            </div>
        )
    }
}
